How Much Hiss Is Normal?


I have some Quad 12L Actives that I'm still setting up. I notice an ever so slight hiss from the speaker even when it's not connected to anything. You have to be right next to the speaker to hear it though. The volume setting does not change this. I'm reading that this is not uncommon for (other) powered speakers. They are both connected to a power cord surge suppressor. I assume this is normal??
ktennis
If you have tube equiptment, a hum is all to common. Even you can hear noise from SS amps. The king of hiss is my beloved Reel to reel 4 track. However, if it does not interfere with your listening experience I wouldn't worry about it.
My rule of thumb regarding hiss is that it should never be more than 10% the spl of the total harmonic distortion of the amplifier driven to RMS clipping into the load you’re listening to. If it’s under that figure, usually you’re fine. If it’s over, you should be concerned: very concerned.
I have two pair of Quad 12L Pro Actives and every speaker has some hiss...one or two more than the others. I don't hear a thing at all from more than 2 ft away. From my listening position, it's dead silent and NEVER intrudes upon the music. No sweat at all.